After installing plugin you will see new Contacts Dictionary in JIRA. This dictionary relates to Companies Dictionary. This means that contact can be added to company. Contact Card attributes can be configured by JIRA administrator as needed.

(lightbulb) In the Contacts Dictionary settings you can turn on synchronization with JIRA Users Dictionary. It will allow automatic determination of company when creating JIRA issue.

Contacts Dictionary

Contact Card

Contacts Related with the Company